During the proposed renewal period, we hope to continue our past focus on novel neurotransmitters and extracellular messengers. The research design provides details regarding work on neuronal nitric oxide synthase associated proteins and D-serine. We will also pursue the inositol polyphosphates, IP7 and IP8, with a special interest in their potential to phosphorylate selected proteins. We will continue studies of heme oxygenase products, CO, iron and biliverdin-bilirubin, as well as poly(ADP-ribose) polymerase (PARP) and its role in normal cell function, as well as cell death. We will also continue our efforts characterizing neural roles of immunophilins, protein 4.1, CAIN and other cytoskeletal proteins.